Antioxidant Activity of Phenolic Compounds of the Cladodes of Opuntia ficus-indica Mill. from Northwest Algeria

The young stems of Opuntia ficus-indica.L, known as cladodes are widely consumed in the world, and appreciated for their high content of fibre and beneficial effects in the metabolism of glucose. The antioxidant activity of total polyphenols, flavonoids and tannins extracts of Oputia ficus-indica grown in Algeria were investigated by using invitro antioxidant models including 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay, reducing power and total antioxidant capacity. The quantitative estimation showed that cladodes were rich in polyphenols which the predominant part is represented by flavonoids (11.86mgCE /gDW) followed by the tannins (6.45mg/g). Our results demonstrate clearly that all extracts have antioxidant capacity. Among these extracts, the ethyl acetate fraction of flavonoids exhibited strong scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) with IC50 values ranged from(0,6 to 5,3mg/ml), and reducing power than the diethyl ether fraction and n-butanol fraction of flavonoids. Opuntia ficus-indica cladodes extracts contain high amounts of polyphenols with strong antiradical, antioxidant capacity and reducing properties which might constitute an important source of natural antioxidants.